Honours Project Opportunities with Nate Lo

Project 1: Evolution of the heaviest cockroach on earth

Supervisors: Nate Lo & Simon Ho

How did Australia’s unique fauna evolve? Macropanesthia rhinoceros is an endemic Australian cockroach, and also the world’s heaviest. Its range is from outback northern Queensland all the way across to the Great Barrier Reef. It digs burrows in the soil up to one metre deep, and gives birth to live young, both very unique traits among cockroaches. Unlike its pest relatives, M. rhinoceros is quite charismatic, being wingless, slow moving, and having a strict diet of eucalyptus leaves. The aim of this project is to study how and when this species evolved, by sequencing its DNA and performing phylogenetic comparisons with related cockroaches. One hypothesis that is it evolved from wood-dwelling, rainforest cockroach species, and developed its unique traits as a result of increasing aridity in Australia over the last 15 million years. The student will gain experience with molecular ecological techniques, and computational techniques used in evolutionary biology

Project 2: Polygamy in termites: why do some termite colonies have only one king and queen, and others multiple kings and queens?

Supervisors: Nate Lo & Ben Oldroyd

In most termite species studied, colonies are formed by one queen and king, who then have up to a few million offspring. However, in colonies Nasutitermes exitiosus – a species found in Sydney - colonies often have multiple kings and queens. This is expected to lead to some conflict between the parents for their share in reproduction, and the reasons for its evolution are unknown. One possibility is that under difficult ecological conditions it is easier to form a colony with multiple reproductives rather than just two. This project involves the use of field work, microsatellites and mitochondrial DNA to determine the number of kings and queens in N. exitiosus colonies, and examination of the conditions under which they are found. Tests will be performed also test for potential reproductive conflicts between multiple queens and kings

Project 3: The role of junk DNA in termite biology

Supervisor: Nate Lo

Biology has yielded many surprises, but one of the greatest has been the discovery that standard protein-coding genes in animal genomes represent only a small fraction of the genome size, sometimes less than 2%. A large fraction of the genome consists of repetitive elements, which for a long time have been considered “junk DNA”. We have discovered repetitive elements in termites that appear to play an important role in termite biology. This project will involve examining the expression of these repetitive elements, and silencing their expression to look for phenotypic effects.

Project 4: Are Australian ticks spreading Lyme disease?

Supervisor: Nate Lo

Ticks are obligate bloodsucking arthropods second only to mosquitoes as worldwide vectors of human diseases. A number of Ixodes spp., including the paralysis tick I. holocyclus, have geographic distributions along the east coast of Australia, overlapping with the bulk of the human population. The presence in Australia of Lyme borreliosis - the most common tick-borne disease in the world - is controversial. Lyme is caused by at least three species of the spirochete genus Borrelia. On the basis of studies on ticks during the 1990s, the current advice from the NSW Health Service is that there is “no evidence for the presence of Lyme borreliosis in Australia”. However, there have been many cases of tick-bite victims in Australia who have developed Lyme-like disease symptoms, and number of medical experts believe that the disease is present her. In this project you will use molecular techniques to examine Australian ticks for the presence of Borrelia and other potential pathogens.